This invention pertains to the electrowinning of metal and more in particular relates to a means to introduce a feed material into an electrolytic cell for producing a metal from metal ions in a fused salt bath.
Metals, such as titanium, have previously been electrolytically recovered from, for example, titanium tetrachloride in a fused salt bath, such as a mixture of potassium and lithium chlorides, in an electrolytic cell containing an anode, cathode and a means to supply metal ions to the bath. Such processes are generally described in, for example, Leone et al., High-Purity Titanium Electrowon from Titanium Tetrachloride, J. of Metals 18 (March 1967); Leone et al., Use of Composite Diaphragms in the Electrowinning of Titanium, Bureau of Mines Report RI 7648 (1972) and U.S. Pat. Nos. 2,789,943; 2,943,032 and 3,082,159. These processes produce generally satisfactory titanium by, for example, bubbling titanium tetrachloride gas directly into a molten lithium chloride-potassium chloride catholyte, reducing the titanium ion and depositing metallic titanium on the cathode and releasing chlorine at the anode. However, an improved means of introducing or feeding a multivalent metal into a molten salt bath of an electrolytic cell is desired.